Effect of Alumina Nanoparticles on Texture and Superhydrophobicity of Electrodeposited Hierarchical Nickel-Alumina Nanocomposite Coatings

The electrodeposition technique fabricated hierarchical nickel-alumina nanocomposite coatings on copper. analytical grades of nickel (ii) chloride hexahydrate, i.e., nickel precursor, boric acid, i.e., ph buffer, and ammonium chloride, i.e., crystal modifier, were dissolved in deionized water at 60 °c with concentrations of 200, 150, and 30 g/l, respectively. the alumina nanoparticles with < 25 nm in size were dispersed in the bath with concentrations of 0, 15, 30, and 45 g/l using a magnetic stirrer at 400 rpm speed for 30 min at 60 °c. surface functionalization with stearic acid (0.006 m) was carried out to achieve wetting angles above 150° corresponding to the electrodeposited coatings. field-emission scanning electron microscopy (fesem) and x-ray diffraction (xrd) techniques characterized the coatings' morphology, phases, and texture. the correlation between the alumina content and the contact angle of water droplets on the coatings was elucidated. crystallographic texture coefficients of (111), (200), and (220) crystallographic planes of the nickel phase were calculated using xrd patterns, and the preferred crystallographic growth orientation of the coatings was determined. in a nutshell, the alumina reinforcing phase in the nanocomposite coatings decreased the contact angle compared to pure nickel, although the variation was negligible. in nanocomposite coatings, a positive correlation between alumina concentration in the bath and the contact angle of water droplets on the coatings was noticeable. either pure nickel or nickel-alumina coatings were preferentially grown along the (220) diffraction planes. on the other hand, the growth along the (200) and (111) diffraction planes was randomly oriented.

Effect of alumina nanoparticles on texture and superhydrophobicity of electrodeposited hierarchical nickel-alumina nanocomposite coatings

The electrodeposition technique fabricated hierarchical nickel-alumina nanocomposite coatings on copper. Analytical grades of nickel (II) chloride hexahydrate, i.e., nickel precursor, boric acid, i.e., pH buffer, and ammonium chloride, i.e., crystal modifier, were dissolved in deionized water at 60 °C with concentrations of 200, 150, and 30 g/L, respectively. The alumina nanoparticles with < 25 nm in size were dispersed in the bath with concentrations of 0, 15, 30, and 45 g/L using a magnetic stirrer at 400 rpm speed for 30 min at 60 °C. Surface functionalization with stearic acid (0.006 M) was carried out to achieve wetting angles above 150° corresponding to the electrodeposited coatings. Field-emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD) techniques characterized the coatings' morphology, phases, and texture. The correlation between the alumina content and the contact angle of water droplets on the coatings was elucidated. Crystallographic texture coefficients of (111), (200), and (220) crystallographic planes of the nickel phase were calculated using XRD patterns, and the preferred crystallographic growth orientation of the coatings was determined. In a nutshell, the alumina reinforcing phase in the nanocomposite coatings decreased the contact angle compared to pure nickel, although the variation was negligible. In nanocomposite coatings, a positive correlation between alumina concentration in the bath and the contact angle of water droplets on the coatings was noticeable. Either pure nickel or nickel-alumina coatings were preferentially grown along the (220) diffraction planes. On the other hand, the growth along the (200) and (111) diffraction planes was randomly oriented.